Precipitation of pseudo-boehmite particles is experimentally investigated. The experiments have been carried out in three chemical reactors specially designed to achieve an effective control of the properties of mineral particles produced by precipitation. The chemical reactors are the Sliding-Surface Mixing Device, the Special Rushton Turbine Reactor and the Vortex Effect Reactor. The mixing efficiency of these new mixing devices is experimentally evaluated and the influence of reactor geometries, operating parameters and initial supersaturation on pseudo-boehmite particle properties is studied. The particle properties evaluated are particle size distribution, crystallite size, BET surface area, porous volume, mean pore radius and particle shape. A comparison of the particle properties obtained with the three reactors is made.